Remove Julia version from Documenter workflow

Removed specific Julia version specification from setup.

Author: RGerzaguet

.github/workflows/Documenter.yml

@@ -13,8 +13,6 @@ jobs:
     steps:
       - uses: actions/checkout@v2
       - uses: julia-actions/setup-julia@latest
-        with:
-          version: '1.9'
       - name: Install dependencies
         run: julia --project=docs/ -e 'using Pkg; Pkg.develop(PackageSpec(path=pwd())); Pkg.instantiate()'
       - name: Build and deploy